The two remaining holes on the leading edge side of the middle nose rib were dimpled using Cleaveland's tight fit dimpling fixture mounted to the workbench. The dimples were formed with the female dimple die on the fixture, and the male dimple die held in place by hand underneath the rivet gun and back rivet set. Then the dimple depth was checked using a 426 rivet to ensure that the rivet head is flush with the skin surface.The rest of the evening was spent with the pneumatic squeezer dimpling the side flanges on the ribs (except the same fairing attach holes on the lower ribs, previously marked on the skin), the front spar, and the rear spar (only the uppermost holes, as per plans). Since it was getting late, I didn't want to commence noisy counter-sink operations, so I set up the #40 countersink bit and cage for tomorrow and then worked ahead in the plans. I match-drilled and deburred the front spar doubler and separated the rudder stop parts on the bandsaw in preparation for attachment to the rudder hinge brackets.
Tight Fit Dimpling Fixture Mounted to Workbench
Using Back Rivet Set and Male Dimple Die to Dimple Hard to Reach Holes
